/*
 * Copyright 2011 Clean GWT
 * 
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
 * in compliance with the License. You may obtain a copy of the License at
 * 
 * http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software distributed under the License
 * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
 * or implied. See the License for the specific language governing permissions and limitations under
 * the License.
 */
package com.cleangwt.json.client;

import java.util.Collection;
import java.util.Date;
import java.util.Map;

import com.google.gwt.json.client.JSONBoolean;
import com.google.gwt.json.client.JSONNumber;
import com.google.gwt.json.client.JSONString;
import com.google.gwt.json.client.JSONValue;

/**
 * The generic json serializer.
 * 
 * @author Jess
 * @version 1.0
 * @since 1.0
 */
public class ObjectSerializer extends JsonValueSerializer<Object> {
  private static ObjectSerializer impl;

  /**
   * @return the instance of generic serializer
   */
  public static ObjectSerializer get() {
    if (impl == null) {
      impl = new ObjectSerializer();
    }
    return impl;
  }

  private ObjectSerializer() {
  }

  @SuppressWarnings({"rawtypes", "unchecked"})
  @Override
  public JSONValue toJson(Object value) {
    if (value instanceof String) {
      return new JSONString((String) value);
    } else if (value instanceof Number) {
      return new JSONNumber(((Number) value).doubleValue());
    } else if (value instanceof Boolean) {
      return JSONBoolean.getInstance((Boolean) value);
    } else if (value instanceof Date) {
      return new JSONNumber(((Date) value).getTime());
    } else if (value instanceof Map) {
      return MapSerializer.get().toJson((Map<String, Object>) value);
    } else if (value instanceof SimpleObject) {
      return SimpleObjectSerializer.get().toJson((SimpleObject) value);
    } else if (value instanceof Collection) {
      return CollectionSerializer.get().toJson((Collection) value);
    }
    throw new IllegalArgumentException("Unsupported type : " + value.getClass().getName());
  }
}
